Headache is a common symptom in daily life. Almost everyone will have headache in lifetime. The causes of headache are varied. By now, there are a lot of drugs for treating headache abroad or in China, most of which, however, focus on symptomatic treatment of stopping ache (in very few cases, headache is treated by surgery). The results are not satisfactory, because the drugs focus on symptomatic treatment rather than root cause. As a result of this, headache attacks patients recurrently. Long-term use of analgesic agents may cause drug resistance and addiction, so the drug of this kind should not be used for long time. Yet, the headache cannot be cured radically. Besides, according to conditions with different causes, there are different sorts of drugs applied clinically, e.g. the anti-anxiety agent, anti-depressant agent, sympathetic inhibitor, calcium channel blockers and antiepileptic agents etc. Due to their severe side effects, long-term administration will make their efficacy reduced so much that the patients have to increase dose of drug gradually. The result, however, is not satisfactory. The more drugs they take, the severer the headache is. Now, Zhengtian pill (Zhengtianwan) is a Traditional Chinese medicine (TCM) whose formula comprises both TCM and chemical drug. The TCM works by a mechanism of activating blood by removing stasis and the chemical drug stopping pain. In practice, its curative effect is not definite to achieve the purpose of curing radically. Now, there are a lot of TCMs for treating headache. But most of them take effect more slowly; and this drawback will influence life quality of the patients.
Chinese Patent (No. ZL 93100050.5) disclosed a medicinal composition comprising 11 TCMs of Radix Angelicae Sinensis (Dang gui) and Rhizoma Chuanxiong (Chuan xiong), Radix Paeoniae alba (Bai shao), Radix Rehmanniae Preparata (Shu dihuang), Ramulus Uncariae cum Uncis (Gou teng), Caulis Spatholobi (Ji Xueteng), Spica Prunellae (Xia Kucao), Semen Cassiae (Jue mingzi), Concha Margaritifera Usta (Zhen zhumu), Rhizoma Corydalis (Yuan hu) and Asarum herb (Xi xin). It is the fruits of long-term clinical practice under the guidance of Chinese medicine theory, having the therapeutic effects of treating headache caused by inner damage. Clinically, it can be applied to treat several headache diseases, such as the angioneurotic headache, migraine, and some symptoms like dizziness and headache etc. caused by hypertension. According to the proportion of this recipe, the granule of this composition is produced by Tasly Pharmaceutical Group Co. Ltd., named as “Yang Xue Qing Nao Granule”. The functions and indications approved by the authorities are nourishing blood and calming liver, activating blood and removing obstruction in channels, used for diverse types of headache elicited by blood deficiency and hyperactivity of liver, traumatic cranial nerve syndrome, dizziness and vertigo, vexation and irritation, insomnia and dreaminess. In clinic, it has been usually used for treatment headache caused by blood deficiency, blood stasis, and deficiency of Yin and hyperactivity of Yang. Since coming into the market, Yang Xue Qing Nao Granule has gained wide popularity among the patients due to its reassured therapeutic effects.
Now, it has been literally reported that the Yang Xue Qing Nao Granule is usually prepared by the following method. The 11 TCMs are extracted with water, which is precipitated with ethanol to give the extract, and then the extract is mixed with excipients to prepare into various kinds of pharmaceutical formulations. For example, Chinese patents (No. 03140844.3, 200410019825.4) disclosed a process that the 11 TCMs were mixed in proportion, extracted with water for 3 times, combined to get an extract after appropriate concentration, which was added with 2 fold of ethanol to leave it to stand still for 24 hours to precipitate to get supernatant. The supernatant was concentrated to an extract with relative density of 1.3˜1.4. The yield rate was 10%. Aforesaid extract was mixed with sucrose and dextrin in a proportion of 1:3:1 to make granule.
However, due to the different nature of each TCM, the extraction of active ingredients by using method of extracting all together usually results in the extraction incomplete or raises the defect of low yield rate. For example, main ingredients of Radix Angelicae Sinensis (Dang gui) and Rhizoma Chuanxiong (Chuan xiong) are ethanol soluble, so the ethanol was better. In the same manner, the Ramulus Uncariae cum Uncis contains a variety of indole alkaloids, which is dominated by rhynchophylline and isorhynchophylline and a small amount of flavone constituents. Its water decoction and extract are proved to have significantly bio-active effects of sedation, analgesia and antihypertension. Thus, the extraction by water is a more suitable.
As shown in Chinese patents (200510073290.3 and 200510014828.3), 11 TCMs were disclosed, in which Radix Angelicae Sinensis, Rhizoma Chuanxiong, Radix Paeoniae alba and Rhizoma Corydalis were refluxed with ethanol to have a refluxing solution, the residue was mixed with the other 6 TCMs (excluding Ramulus Uncariae cum Uncis) including Radix Rehmanniae Preparata etc. and extracted with water for 3 times. During the process of 3rd decoction, the Ramulus Uncariae cum Uncis was added, and the extraction liquid was combined to concentrate in vacuum. Ethanol was used to precipitate and the obtained solution was left standing still. After being filtered, the filtrate was mixed with aforesaid refluxing solution, and ethanol was recovered under reduced pressure, concentrated and dried to obtain the extract.
In practice, however, extracting Radix Paeoniae alba combined with other TCMs will result in the final extract somewhat less in melting ability. Later addition of the Ramulus Uncariae cum Uncis into the extract may get the medicine float on the surface, so as to influence the extraction. Not only that, but the operation is complicated with the risk of dangerous steam. Extraction of Semen Cassiae by water is prone to cause problems of paste extracting tank or difficult draining.
In view of aforesaid problems, after repeated experimental researches, a new preparation method and a medicinal composition made by this new method have been developed.